1. Field of the Invention
The present invention relates to utility revenue meters for measuring usage and quality of electrical power in an electrical power distribution network. In particular, the present invention relates to utility revenue meters that are connected to the Internet via wireless means.
2. Discussion of the Related Art
With proliferation of electrically powered devices and systems, there is an increasing need to accurately and precisely measure and monitor the quality of the electrical power supplying these devices and systems. Electric utility companies (“utilities”) track electric usage by customers by using electrical energy meters. These meters track the amount of energy consumed at a particular location. These locations range from power substations, to commercial businesses, to residential homes. The electric utility companies use the energy meters to charge customers for their power consumption, i.e. revenue metering.
A popular type of energy meter is the socket-type energy meter. As its name implies, the meter itself plugs into a socket for easy installation, removal, and replacement. Other meter installations include panel mounted, switchboard mounted, and circuit breaker mounted. Typically the energy meter connects between utility power lines supplying electricity and a usage point, namely a residence or commercial place of business. Though not typical, an energy meter may also be placed at a point within the utility's power grid to monitor power flowing through that point for distribution, power loss, or capacity monitoring. Also, energy meters that handle sub-metering functions can be used to monitor internal customer usage.
Traditionally, energy meters used mechanical means to track the amount of consumed power. The inductive spinning disk energy meter is still commonly used. The spinning disk drives mechanical counters that track the power consumption information. Newer to the market are electronic energy meters based on solid-state microprocessor applications. Electronic meters have replaced the older mechanical meters, and utilize digital sampling of the voltage and current waveforms to generate power consumption information. In addition to monitoring power consumption, electronic meters can also monitor and calculate power quality, that is, voltage, current, real power, reactive power, apparent power, etc. These power quality measurements and calculations are displayed on an output display device on the meter.
While electrical utility companies currently use devices to measure the amount of electrical power used by both residential and commercial facilities and the quality of electrical power in an electrical power distribution network, these devices generally do not allow for readings to be made automatically via some remote means. The meter readings are collected in the same manner they were collected in the past, a person reads and reports the information displayed on the meter.
In more recent developments, limited power consumption information can be transmitted from the energy meter to the utility through the use of telephone communications circuitry contained either within or external to the meter. These developments are advantageous to the utility company in that they reduce the need for employees being dispatched to the remote locations to collect the power consumption information. A standard modem receives raw power consumption information from the energy meter and transmits the information to the utility company via telephone lines.
FIG. 1 illustrates a house or an institution 10 having a revenue meter 12 connected to a modem 14. The modem 14 is, in turn, connected to a telephone line 16. In the house or an institution 10, the telephone line 16 may be a dedicated line, i.e., only the modem 14 is connected to it, or a shared line, for example, with one or more telephones 18 connected to the same line 16 via a telephone jack 17. The telephone line 16 is connected to the telephone infrastructure or grid 28 being managed by a telephone company 26. Similarly, on the utility side, the utility company or a department entrusted to receive meter readings 20 includes at least one computer 22 connected to a modem 24, which is connected to the telephone line 16.
While this represents an improvement over past techniques, this method has proven to be costly and unreliable, as there is a need for dedicated telephone line connection and line maintenance, which is expensive. When equipment malfunctions an employee must be dispatched to determine the reason for the malfunction and then a specialist must be sent in to fix it. Therefore, there exists a need for a device, which can accurately, inexpensively, and timely provide measurements, e.g., power consumption information, recorded by a common energy or energy meter.